Printed circuit board and probe therewith

ABSTRACT

Disclosed herein arc a printed circuit board (PCB) and a probe including the same. The probe includes a transducer, a PCB having a pattern part contacting the transducer via face-to-face contact, and a bonding member bonding the transducer to the pattern part of the PCB. The bonding part of the PCB is provided with the pattern part to increase a bonding area of the bonding part and to allow the bonding member to contact not only a metal layer of the bonding part but also an electrical insulation part thereof, thereby improving a bonding force between the transducer and the PCB. As a result, the transducer can be reliably bonded to the PCB, so that performance of the transducer can be prevented from being deteriorated due to defective connection between the PCB and the transducer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.12/607,571, filed on Oct. 28, 2009, which claims the benefit of KoreanPatent Application No. 10-2008-0106259, filed on Oct. 29, 2008, theentire contents of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a printed circuit board (PCB) and, moreparticularly, to a PCB and a probe including the same for use in anultrasound system that generates internal images of a patient body withultrasound waves.

2. Description of the Related Art

Generally, an ultrasound system refers to a non-invasive apparatus thatirradiates an ultrasound signal from a surface of a patient body towardsa target internal organ beneath the body surface and obtains an image ofa monolayer or blood flow in soft tissue from information in thereflected ultrasound signal (ultrasound echo-signal). The ultrasoundsystem has been widely used for diagnosis of the heart, the abdomen, theurinary organs, and in obstetrics and gynecology due to various meritssuch as small size, low price, real-time image display, and highstability through elimination of any radiation exposure, as comparedwith other image diagnostic systems, such as X-ray diagnostic systems,computerized tomography scanners (CT scanners), magnetic resonanceimagers (MRIs), nuclear medicine diagnostic apparatuses, and the like.

Particularly, the ultrasound system includes a probe which transmits anultrasound signal to a patient body and receives the ultrasoundecho-signal reflected therefrom to obtain the ultrasound image of thepatient body.

The probe includes a transducer, a case with an open upper end, a covercoupled to the open upper end of the case to directly contact the bodysurface of the patient, and the like.

The transducer includes a piezoelectric layer in which a piezoelectricmaterial converts electrical signals into sound signals or vice versawhile vibrating, a coordination layer reducing a difference in soundimpedance between the piezoelectric layer and a patient body to allow asmuch of the ultrasound waves generated from the piezoelectric layer tobe transferred to the patient body as possible, a lens layer focusingthe ultrasound waves, which travel in front of the piezoelectric layer,onto a predetermined point, and a to backing layer blocking theultrasound waves from traveling in a rearward direction of thepiezoelectric layer to prevent image distortion.

The piezoelectric layer includes a piezoelectric device, and signal andground electrodes provided to upper and lower ends of the piezoelectricdevice, respectively. Further, a PCB is bonded to the piezoelectriclayer to be connected to the signal and ground electrodes in such a waythat a bonding surface of the PCB is bonded to the ground electrode byan adhesive.

In such a probe, a bonding force between the piezoelectric device andthe bonding surface of the PCB is low to cause unreliable bondingbetween the PCB and the piezoelectric layer, thereby deterioratingperformance of the probe. Therefore, there is a need for an improvedprobe that overcomes such a problem.

SUMMARY OF THE INVENTION

The present invention is conceived to solve the problem of theconventional technique as described above, and an aspect of the presentinvention is to provide an improved probe that can prevent deteriorationof performance caused by defective connection between a piezoelectriclayer and a printed circuit board (PCB).

In accordance with an aspect of the present invention, a probe includes:a transducer; a PCB having a pattern part contacting the transducer viaface-to-face contact; and a bonding member bonding the transducer to thepattern part of the PCB.

The pattern part may include at least one of a polygonal pattern, atransverse line pattern, a lengthwise line pattern, an oblique linepattern, a circular pattern, an elliptical pattern, and a wave pattern.

The pattern part may include a convex portion.

The pattern part may include a concave portion.

In accordance with another aspect of the present invention, a PCBincludes: a bonding part contacting an object via face-to-face contact;and a pattern part provided to the bonding part.

The pattern part may include at least one of a polygonal pattern, anoblique line pattern, a transverse line pattern, a lengthwise linepattern, a circular pattern, an elliptical pattern, and a wave pattern.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of the presentinvention will become apparent from the following description ofexemplary embodiments given in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a schematic cross-sectional view of a probe according to anembodiment of the present invention;

FIG. 2 is a view of a PCB shown in FIG. 1;

FIGS. 3 to 7 are views of PCBs according to various embodiments of thepresent invention; and

FIG. 8 is a schematic cross-sectional view of a probe according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENT

Exemplary embodiments of the present invention will now be described indetail with reference to the accompanying drawings. It should be notedthat the drawings are not to precise scale and may be exaggerated inthickness of lines or size of components for descriptive convenience andclarity only. Furthermore, terms used herein are defined by takingfunctions of the present invention into account and can be changedaccording to the custom or intention of users or operators. Therefore,definition of the terms should be made according to overall disclosuresset forth herein.

FIG. 1 is a schematic cross-sectional view of a probe according to anembodiment of the present invention, and FIG. 2 is a view of a PCB shownin FIG. 1.

Referring to FIGS. 1 and 2, a probe 100 according to the embodiment ofthe invention includes a transducer 110, a PCB 120, and a bonding member130.

The transducer 110 transmits an ultrasound signal to a patient body andreceives the ultrasound echo-sound reflected therefrom. The transducer110 includes a piezoelectric layer 112 in which a piezoelectric materialconverts electrical signals to sound signals or vice versa whilevibrating. The piezoelectric layer 112 includes a piezoelectric device112 a, which generates ultrasound waves through a resonance phenomenon,and signal and ground electrodes 112 b and 112 c provided to upper andlower ends of the piezoelectric device 112 a, respectively.

The piezoelectric device 112 a may be formed of a ceramic of leadzirconate titanate (PZT), a PZNT single crystal made of a solid solutionof lead zinc niobate and lead titanate, a PZMT single crystal made of asolid solution of lead magnesium niobate and lead titanate, or the like.Further, the signal and ground electrodes 112 b and 112 c may be formedof a material having good electrical conductivity, such as gold, silver,or the like.

Further, the transducer 10 includes a coordination layer 114, which isformed of glass or resin materials and reduces a difference in soundimpedance between the piezoelectric layer 112 and the patient body so asto allow as much of the ultrasound waves generated from thepiezoelectric layer 112 to be transferred to the patient body aspossible, a lens layer 116 focusing the ultrasound waves, which travelin front of the piezoelectric layer 112, onto a predetermined point, anda backing layer 118 blocking the ultrasound waves from traveling in arearward direction of the piezoelectric layer 112 to prevent imagedistortion.

The PCB 120 is provided substantially perpendicular with respect to thelamination direction of the transducer 110. An example of the PCB 120 isa flexible printed circuit board (FPCB). The PCB 120 includes a bondingpart 122 and a line electrode part 124.

The bonding part 122 contacts the piezoelectric layer 112 of thetransducer 110, more specifically, a lateral side of the piezoelectricdevice 112 a of the piezoelectric layer 112. The bonding part 122includes a flexible electrical insulation film, and a metal layer formedon the electrical insulation film.

The line electrode part 124 includes a signal line electrode 124 a and aground line electrode 124 b. The signal line electrode 124 a and theground line electrode 124 b are disposed corresponding to the signalelectrode 112 b and the ground electrode 112 c of the piezoelectriclayer 112, respectively. The signal line electrode 124 a and the groundline electrode 124 b are soldered to the signal electrode 112 b and theground electrode 112 c by a solder such as lead or the like,respectively, thereby electrically connecting the piezoelectric layer112 to the PCB 120.

On the other hand, the bonding part 122 is bonded to the lateral side ofthe piezoelectric device 112 a via a bonding member 130. The bondingmember 130 is made of a non-conductive material to insulate the signalelectrode 112 b from the ground electrode 112 c while bonding thepiezoelectric device 112 a to the bonding part of the PCB 120. Thebonding member 130 may be an adhesive deposited between the bonding part122 and the piezoelectric device 112 a to form a bonding layertherebetween. Bonding between the bonding part 122 and the piezoelectricdevice 112 a allows the PCB 120 to be bonded to the transducer 110.

The bonding part 122 is provided with a pattern part 125. The patternpart 125 is partially formed on the bonding part 122 or is formed overthe entire surface of the bonding part 122. The pattern part 125 isprovided to be in face-to-face contact with the piezoelectric layer 112when the PCB 120 is bonded to the piezoelectric layer 112. The patternpart 125 is formed by etching the metal layer formed on the electricalinsulation film of the bonding part 122 such that the electricalinsulation film can be exposed in a predetermined shape.

According to this embodiment, the pattern part 125 is illustrated asincluding a predetermined pattern, more specifically, a rhombus pattern.The rhombus pattern may be formed in a convex portion 125 a or a concaveportion 125 b on the bonding part 122. Here, the convex portion 125 acorresponds to a portion where the metal layer is formed, and theconcave portion 125 b corresponds to a portion where the electricalinsulation film is exposed.

In the probe 100 of this embodiment, the pattern part 125 is provided tothe bonding part 122 of the PCB 120 bonded to the piezoelectric device112 a, as described above, so that the bonding part 122 has an increasedbonding area and the bonding member 130 can come into contact with notonly the metal layer of the bonding part 122 but also the electricalinsulation film thereof, thereby enhancing the bonding force between thetransducer 110 and the PCB 120.

In the probe 100 according to this embodiment, the transducer 110 andthe PCB 120 can be more reliably bonded to each other, therebypreventing performance deterioration of the probe 100, which can becaused by defective connection between the transducer 110 and the PCB120.

In the above description, the pattern part 125 is illustrated asincluding the rhombus pattern, but the present invention is not limitedthereto.

FIGS. 3 to 7 are views of PCBs according to various embodiments of thepresent invention.

For convenience of description, the same or similar configurations asthose of the above embodiment will be indicated by the same referencenumerals, and detailed descriptions thereof will be omitted herein.

Referring to FIGS. 3 to 7, PCBs 220, 320, 420, 520 and 620 may have apattern part 225 including an oblique line pattern as shown in FIG. 3, apattern part 325 including a polygonal pattern of a rhombus shape asshown in FIG. 4, a pattern part 425 including a polygonal pattern of arectangular shape as shown in FIG. 5, a pattern part 525 including atransverse line pattern as shown in FIG. 6, and a pattern part 625including a lengthwise line pattern as shown in FIG. 7, respectively.Additionally, although not shown in the drawings, the pattern part maybe realized in various modifications including a circular pattern, anelliptical pattern, a wave pattern, and the like.

FIG. 8 is a schematic cross-sectional view of a probe according toanother embodiment of the present invention.

Referring to FIG. 8, a probe 700 according to this embodiment includes atransducer 710 and a PCB 720.

In FIG. 8, the transducer 710 includes a piezoelectric layer 712, acoordination layer 714, a lens layer 716, and a backing layer 718. Thepiezoelectric layer 712, coordination layer 714, lens layer 716, andbacking layer 718 are stacked to constitute a laminate. Theconfiguration and operation of the transducer 710 are similar to thoseof the transducer 110 (see FIG. 1) according to the above embodiment,and a detailed description thereof will be omitted.

The PCB 720 is provided substantially in the horizontal direction withrespect to the lamination direction of the transducer 710, and includesa bonding part 722 and a line electrode part 724.

The bonding part 722 contacts an upper or lower side of a piezoelectriclayer 712. The bonding part 722 includes a flexible electricalinsulation film, and a metal layer formed on the electrical insulationfilm.

The line electrode part 724 includes a signal line electrode 724 a and aground line electrode 724 b. The signal line electrode 724 a and theground line electrode 724 b are disposed corresponding to a signalelectrode 712 b and a ground electrode 712 c of the piezoelectric layer712, respectively. The signal line electrode 724 a and the ground lineelectrode 724 b are soldered to the signal electrode 712 b and theground electrode 712 c by a solder such as lead or the like,respectively, thereby electrically connecting the piezoelectric layer712 to the PCB 720.

On the other hand, the bonding part 722 is bonded to the upper or lowerside of the piezoelectric layer 712 via a bonding member (not shown).The bonding member bonds the bonding part 722 of the PCB 720 to thepiezoelectric layer 712. The bonding member may be a non-conductiveadhesive deposited between the bonding part 722 and the piezoelectriclayer 712 to form a bonding layer therebetween. Bonding between thebonding part 722 and the piezoelectric layer 712 allows the PCB 720 tobe bonded to the transducer 710.

The bonding part 722 is provided with a pattern part (reference numeralomitted). The pattern part is partially formed on the bonding part 722or is formed over the entire surface of the bonding part 722. Thepattern part is provided to be in face-to-face contact with thepiezoelectric layer 712 when the PCB 720 is bonded to the piezoelectriclayer 712. The pattern part is formed by etching the metal layer formedon the electrical insulation film of the bonding part 722 such that theelectrical insulation film of the bonding part can be exposed in apredetermined shape. The configuration and operation of the pattern partare similar to those of the pattern parts 125, 225, 325, 425, 525 and625 shown in FIGS. 2 to 7, and a detailed description thereof will beomitted herein.

As apparent from the above description, according to the embodiment ofthe present invention, a bonding part of the PCB is provided with apattern part to increase a bonding area of the bonding part and to allowa bonding member to contact not only a metal layer of the bonding partbut also an electrical insulation part, thereby improving a bondingforce between a transducer and the PCB. As a result, the transducer canbe reliably bonded to the PCB, so that performance of the transducer canbe prevented from being deteriorated due to defective connection betweenthe PCB and the transducer.

Although the present invention has been described with reference to theembodiments shown in the drawings, it will be apparent to those skilledin the art that the embodiments are given by way of illustration only,and that various modifications and equivalent embodiments can be madewithout departing from the spirit and scope of the present invention.Accordingly, the scope of the present invention should be limited onlyby the accompanying claims.

1. A probe comprising: a transducer; a printed circuit board (PCB)having a pattern part contacting the transducer via face-to-facecontact; and a bonding member bonding the transducer to the pattern partof the PCB.
 2. The probe according to claim 1, wherein the pattern partcomprises at least one of a polygonal pattern, a transverse linepattern, a lengthwise line pattern, an oblique line pattern, a circularpattern, an elliptical pattern, and a wave pattern.
 3. The probeaccording to claim 1, wherein the pattern part comprises a convexportion.
 4. The probe according to claim 1, wherein the pattern partcomprises a concave portion.
 5. A printed circuit board (PCB)comprising: a bonding part contacting an object via face-to-facecontact; and a pattern part provided to the bonding part.
 6. The PCBaccording to claim 5, wherein the pattern part comprises at least one ofa polygonal pattern, an oblique line pattern, a transverse line pattern,a lengthwise line pattern, a circular pattern, an elliptical pattern,and a wave pattern.